Electric furnace.



No. 779,844. PATENTED JAN. 10, 1905.

' D. R. S. GALBRAITH.

ELECTRIC FURNACE.

APPLIUATIOK FILED OUT. 27, 1903.

UNITED STATES Patented January 10, 1905.

PATENT OFFICE.

ASSIGNOR OF ONE-HALF TO NVILLIAh I NEW ZEALAN D.

STEUART, OF AUCKLAND,

ELECTRIC FURNACE.

SPECIFICATION forming part of Le Patent No- 779,844, dated January 10, 1905.

Application filed October 27,1903. Serial No. 178,787.

To a whom, it may concern.-

Be it known that I, DAVID RANKEN SHIR- REFF GALBRAITH, analytical and consulting chemist, Fellow of the Institute of Chemistry of Great Britain and Ireland, of The Ladies Mile, Auckland, New Zealand, have invented certain new and useful Supplementary Apparatus for the Reduction of Iron-Sand, Iron (kids, and other Suitable Substances, of which the following is a specification.

This invention relates to an electrical furnace for the treatment of iron-sand and other refractory ores or metal-bearing substances, and has special reference to the treatment and of the arrangement of the fusing zone of the furnace, whereby the shower charge of the material under treatment while being deflected by intercepters crossing the fusing zone is repeatedly caused to complete and act as part of the electric circuit and be raised to incandeseence by reason of its resistance, in consequence whereof the utmost effect incidental to the electric current will be obtained and the treatment will be expedited.

In carrying out the invention the fusing Zone of the furnace laterally stepped is fitted crosswise with a plurality of non-conducting intercepters arranged grid-like in superposed relation, and electric conductors are led at the ends of the intercepters into the fusing Zone, and the shower charge is fed centrally onto the intercepters, so that as the material under treatment falls on and lies along each one of the plurality of superposed intercepters and on and along the electric conductors at its ends the material will electrically connect such conductors and complete the electric circuit and will incandesce by means of its resistance to the electric current.

On the accompanying drawings, Figure 1 represents the furnace and the receiver in sectional elevation. Fig. 2 is a sectional elevation at right angles to Fig. 1, and Fig. 3 is an enlarged sectional perspective view representing the fusing Zone characteristic of this invention.

The apparatus represented in the drawings consists of a furnace a, composed of blocks (Z,

inclosed by casings e a, and. provided with a cap 0* having a feed-hole s, and a crucible IL,

or receiver of the'products of the furnaceinclosed by casings ff, serving as a base to the furnace and having a gas-inlet g with crossing incandescents 2', and slag and metal outlets p q, the furnace and its casing being recessed or chambered at ,7' to accommodate the electric conductors t and terminals 25, and the furnace having the sides of its fusing Zone repeatedly stepped at 712., so as to form guidechutes to deflect and direct the descending iron-sand or other substances.

According to the present invention the ma terial under treatment while traversing the fusing Zone of the furnace showerwise in thin streams is caused to complete and act as part of the electric circuit at the time of or while being deflected in its fall by each respective one of the plurality of intercepters, whereby in its fall it is caused to be repeatedly acted on by the electric currentto the fullest advantage. To attain this end, non-conducting intercepters 0 are placed across the fusing zone in superposed relation and located in recesses y' in the furnace sides, and carbon or other conductors B are adapted to rest on the ends of and to be partly embedded in the intercepters and to project into the furnace fusing zone. V-shaped troughs A, having perforated bottoms, are also arranged across the furnace a short distance above and longitudinally central of the upper intercepters, so as to direct the material under treatment in thin showerlike streams directly thereonto.

The material to be treated after preliminary treatment is fed through the cap feed-hole into the V-troughs, which direct it in streams centrally over the under non-conducting intercepters and their respective end conductors, in consequence whereof while the material rests on the intercepters and conductors it electrically connects the latter and completes the electric circuit and by reason of its resistance is heated to incandescence, such action being repeated in descending succession as the material 18 intercepted and deflected by the successively lower intercepters while the ascending current of reducing-gas delivered from the receiver acts continuously on the material.

The intercepters are made of bauxite or other suitable refractory material and may be made of any suitable form and arranged to be rotatable.

\Vhat I claim as my invention, and desire to secure by Letters Patent. is-

In an electric furnace for treating iron-sand and other refractory ores andsubstances comprising an incased furnace recessed to accommodate electric connections in circuit with a source of electric energy and having the sides of its fusing Zone stepped internally with inclined chutes, a plurality of non-c0nducting intcrcepters mounted Within the furnace at the stepped fusing zone and arranged in superposed relation and adapted together With such stepped parts of the furnace to deflect the 1naterial under treatment successively to the next lower intercepters and with electric conductors leading into the fusing zone at the ends of each intercepter, and a plurality of V- shaped troughs perforated at their bottoms and serving to direct the material in thin streams longitudinally central of the under series of intercepters and conductors, whereby, the shower charge of the material will be caused at the time of each of its in tcrceptions to complete and act as part of the electric circuit, as set forth.

DAVID RANKEN Slllltltl ll ll GAlillltill'lll.

Vitnesses:

GEORGE WILLIAM BASLEY, PERCY HERBERT BASLEY. 

